The present invention is directed to bicycles and, more particularly, to an apparatus for mounting a bicycle electrical component.
Recently, bicycles have been equipped with various electrical components used to facilitate the operation of the bicycle. For example, various electrical devices may be used to operate the bicycle transmission or to provide an assisting force to facilitate pedaling the bicycle. See, for example, Japanese Laid-Open Patent Application No. 2004-90915.
Many bicycles have derailleur operated transmissions. Such transmissions usually include a plurality of front sprockets and a plurality of rear sprockets, wherein the plurality of front sprockets are mounted for rotation coaxially with the pedal cranks, and the plurality of rear sprockets are mounted for rotation coaxially with the rear wheel. A front derailleur is mounted to the bicycle frame in close proximity to the plurality of front sprockets to selectively engage a chain with one of the plurality of front sprockets, and a rear derailleur is mounted to the bicycle frame in close proximity to the plurality of rear sprockets to selectively engage the chain with one of the plurality of rear sprockets.
Electrical devices have been used to control such derailleur operated transmissions. A typical electrically operated derailleur, for example, comprises a housing member mounted to the bicycle, a drive unit such as a motor disposed in the housing member, a gear shift cable connected between the motor and the derailleur, a gear shift controller disposed in the housing member next to the drive unit for controlling the operation of the motor, and a shift control device typically mounted on the bicycle handlebar for providing gear shift signals. The gear shift signals may be provided automatically in response to bicycle speed or manually in response to the operation of a lever or button by the rider. The gear shift controller usually includes a control unit comprising a programmed microprocessor mounted on a flat circuit substrate such as a printed circuit board. The gear shift controller causes the motor to move the gear shift cable in response to the gear shift signals from the shift control device, thereby moving the derailleur to position the chain on the desired sprocket.
In a typical electrically controlled device, the control unit mounted to the flat circuit substrate is disposed adjacent to the drive unit in the housing member. As a result, the housing member must be constructed with a housing space large enough to accommodate both the drive unit and the flat circuit substrate. Because the circuit substrate typically has a square or rectangular shape, the housing member often must be made larger than desired, with needless and wasteful space inside the housing member. The larger housing member also makes the electrically operated component larger and heavier. Since the bicycle is powered by human pedaling, the added weight increases the effort required by the rider.